Bagaimana untuk membangunkan fungsi pengurusan kontrak SuiteCRM melalui PHP

id INT AUTO_INCREMENT PRIMARY KEY,
name VARCHAR(255) NOT NULL,
start_date DATE NOT NULL,
end_date DATE NOT NULL,
amount DECIMAL(10,2) NOT NULL,
status ENUM('draft', 'active', 'completed') NOT NULL DEFAULT 'draft',
created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP

class ContractManager
{
    private $db;

    public function __construct()
    {
        global $db;
        $this->db = $db;
    }

    public function createContract($name, $startDate, $endDate, $amount)
    {
        $sql = "INSERT INTO contracts (name, start_date, end_date, amount) VALUES (?, ?, ?, ?)";
        $stmt = $this->db->prepare($sql);
        $stmt->bind_param("sssd", $name, $startDate, $endDate, $amount);
        $stmt->execute();
        $stmt->close();
    }

    public function updateContract($contractId, $name, $startDate, $endDate, $amount)
    {
        $sql = "UPDATE contracts SET name = ?, start_date = ?, end_date = ?, amount = ? WHERE id = ?";
        $stmt = $this->db->prepare($sql);
        $stmt->bind_param("sssd", $name, $startDate, $endDate, $amount, $contractId);
        $stmt->execute();
        $stmt->close();
    }

    public function deleteContract($contractId)
    {
        $sql = "DELETE FROM contracts WHERE id = ?";
        $stmt = $this->db->prepare($sql);
        $stmt->bind_param("d", $contractId);
        $stmt->execute();
        $stmt->close();
    }

    public function getContract($contractId)
    {
        $sql = "SELECT * FROM contracts WHERE id = ?";
        $stmt = $this->db->prepare($sql);
        $stmt->bind_param("d", $contractId);
        $stmt->execute();
        $result = $stmt->get_result();
        $contract = $result->fetch_assoc();
        $stmt->close();
        return $contract;
    }

    public function getAllContracts()
    {
        $sql = "SELECT * FROM contracts";
        $result = $this->db->query($sql);
        $contracts = [];
        while ($contract = $result->fetch_assoc()) {
            $contracts[] = $contract;
        }
        $result->close();
        return $contracts;
    }
}

require_once('include/ContractManager.php');
$contractManager = new ContractManager();

// 创建合同示例
$contractManager->createContract('合同1', '2021-01-01', '2021-12-31', 10000);

// 更新合同示例
$contractManager->updateContract(1, '合同1 - 修改后', '2021-01-01', '2021-12-31', 15000);

// 删除合同示例
$contractManager->deleteContract(1);

// 获取单个合同示例
$contract = $contractManager->getContract(1);

// 获取所有合同示例
$contracts = $contractManager->getAllContracts();